


Swap!

by ohofcourse



Category: Hunter X Hunter
Genre: Anal Fingering, Anal Sex, Angst and Fluff and Smut, Hurt/Comfort, Light Angst, M/M, Whump, body swap?
Language: English
Status: Completed
Published: 2020-09-09
Updated: 2020-09-09
Packaged: 2021-03-07 02:14:11
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,151
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26369299
Author URL: https://archiveofourown.org/users/ohofcourse/pseuds/ohofcourse
Summary: Hisoka and Illumi wake up to find they have swapped bodies. Hisoka wants to have sex. Illumi just wants to try tea without poison in it.
Relationships: Hisoka/Illumi Zoldyck
Comments: 16
Kudos: 540





	Swap!

**Author's Note:**

> I'm totally procrastinating the two multi-chapter hisoillu fics I'm in the middle of right now :) new chapters are coming out for those soon, though. scouts honor. please enjoy what was supposed to be self-indulgent fluff which turned into self-indulgent smut and angst!

Hisoka woke up with hair in his mouth. This struck him as odd. Never in his life had he woken up with hair in his mouth, not even someone else’s hair. His hand, which felt odd, like it wasn’t connected to his body, reached out, looking for Illumi, who slept on the right side of the bed, further from the bathroom and closer to the floor-to-ceiling windows that covered one wall in their bedroom. But, instead of a warm body or a warm dent in the mattress, his hand flopped over the edge of the bed and grazed the bedside table. 

Hisoka felt a sudden and intense bout of vertigo. 

He was on Illumi’s side of the bed. 

There was no one on his side. Their bathroom light was on, but the door was closed, which was odd. They never had the door closed. Hisoka sat up and flinched. There were whispers of  _ something trailing _ down his back. He cringed and turned around, and then the whispers followed him, sliding down his shoulder and arm and chest now. 

Hair. 

Long, silky, black hair. 

Ah. 

The bathroom door opened slowly. Hisoka knew what he looked like, objectively. In fact, he was, according to Illumi, overly aware of what he looked like, obsessed, perhaps. 

The person in front of him  _ was  _ him, technically, but it simply wasn’t. 

“There is a problem,” his body said. It was Illumi. It was Hisoka’s voice and body, but it was undoubtedly Illumi. Hisoka had never realized how much of Illumi’s appearance came from his personality. 

Hisoka’s usually smug face was blank. His eyes were wide and apathetic. The irises were not black or quite as massive as Illumi’s, but they matched his sentiment. 

“Stop doing that with my face,” Hisoka said. Illumi frowned. An Illumi frown on Hisoka’s face was odd. Weirdly appealing. Maybe it was simply novel. 

“This is just my face,” Illumi said. He had not yet gone through Hisoka’s extensive makeup and hair routine, and Hisoka had a feeling he wouldn’t be for as long as they were like this. 

“Is this someone’s nen?” Hisoka mused. He watched his own face contort into a beautiful expression of exasperation. 

“Do I look like I know the answer to that question?” 

“I was thinking out loud,” Hisoka said. 

“As always,” Illumi sighed. Maybe Hisoka should be apathetic more often. It was a good look on him. 

“We need to set ground rules,” Illumi added, settling down on the edge of the bed gracefully. 

“Rules,” Hisoka said slowly, smiling now. 

“We are not masturbating.” 

“That was the first thing I wanted to do, Illu,” Hisoka whined. 

“Yes, I know,” Illumi hissed with Hisoka’s mouth. 

“How is that any different from having sex normally?” 

“It’s  _ very  _ different.” Illumi’s face was serious, so Hisoka relented. 

“Fine, fine, whatever. But we are having sex, I hope you know.” Illumi said nothing, which Hisoka took to mean enthusiastic agreement. 

“What are the other rules?” Hisoka prodded. 

“Don’t--” Illumi sighed, rubbing his brow. “Don’t embarrass me, okay?” Hisoka leaned forward and grinned. Illumi’s mouth did not open the same way his did, and his teeth were straighter: rich boy teeth. 

“How could I embarrass you?” 

“You aren’t taking any jobs,” Illumi began. “And don’t get drunk and dance on a table, or whatever you do.” 

“You’d want to go out like this?” 

“I don’t know how long this is going to last,” Illumi said with a shrug. 

“Okay,” Hisoka said, nodding, “but I have rules, too.” Illumi cocked his head and waited. Even his mannerisms looked wrong on Hisoka’s body. 

“We need to discuss your diet.” Illumi rolled his eyes, another thing that Hisoka usually did not do. 

“No poison, no processed sugar, and you need to eat meals, actual meals, including breakfast.” 

“This is ridiculous,” Illumi said flatly. 

“I’m protecting my body,” Hisoka said. “And I’ll be doing yours a favor, you know. I’ll actually eat a vegetable or something.” 

“You have to keep up with the poison regimen, or you’ll make me vulnerable to assassinations.” 

“Fine.” 

“Fine.” They stared at each other, as if suddenly remembering their predicament. Hisoka got up first, grabbing Illumi’s silk robe from it’s hook by the bathroom. 

“That’s--” Illumi stopped himself. It was his, technically, but Hisoka also had his body right now. 

“I’m going to go make weird faces in the mirror,” Hisoka called, closing the bathroom door behind him. Illumi heard the lock click into place. 

* * *

Hisoka’s body was not a bad place to be stuck in. For one, Illumi’s awful migraines were gone. Two, he was a bit broader than Illumi, and Illumi liked the feeling of being bigger than Hisoka for once, even if it was by the merit of being in his body. 

Hisoka seemed to be enjoying himself, too. Illumi could tell that “making weird faces in the mirror” had actually meant jacking off in the shower. But, he found that he didn’t care that much. Hisoka was already plenty familiar with his body. 

“Illumi,” Hisoka called in his voice. He had bastardized it though, made it smug and whiny and full of emotion. “My head hurts.” He flopped down on the couch. 

“Yeah,” Illumi agreed. “I get migraines.”

“Darling, this is awful.” 

“It doesn’t happen too often, every week or so.” Hisoka gave him a pained look, as if to say that that was too often. 

“I’m making you poisoned tea. It’s too late for caffeine,” Illumi said, stretching like a cat. 

“Does it taste bad?” 

“No.” 

It did taste bad, if Hisoka’s gagging was any indication. 

“You’re being dramatic.” 

“It  _ burns _ !” Hisoka cried. His eyes, Illumi’s eyes, welled up with unshed tears. Illumi poured himself a plain cup of tea and sipped it. 

“Oh, it’s much better without poison. Damn.” 

“I’m just going to drink it like a shot.” 

“It’s hot tea,” Illumi said dubiously. Hisoka glared at him over his shoulder. 

“Drink your tea, Illumi,” he said bitterly, knocking back his own mug with a grimace. As soon as it was empty, he stood, rubbed his tongue on the collar of his shirt, and sank onto one of the stools at the kitchen island. 

“What do you want to do?” He asked. Illumi sipped his tea. 

“Your head doesn’t hurt too much?” 

“It’s fine. You never complain about it.” 

“I’m used to it,” Illumi reminded him. 

“I’m fine, dear,” Hisoka said, pressing a kiss to Illumi’s temple. He made a face immediately after. 

“It’s weird kissing myself.” 

“It’s weird being kissed by myself,” Illumi said. 

“So it cancels out!” Hisoka said, planting a big wet kiss right on Illumi’s mouth. Illumi laughed--Hisoka’s laugh was a bit lower than Illumi’s, but it stuttered like a child’s, more a giggle than a laugh. 

When it became decidedly afternoon, Hisoka dragged Illumi out for a late lunch. Illumi took Hisoka’s body out into public without makeup on, and Hisoka used Illumi’s mouth to smile the whole time. 

By the time they had gotten home, it was beginning to feel natural, seeing their own faces every time they leaned in for a kiss. 

* * *

Day turned to evening and Illumi suddenly got the feeling that something was wrong. Hisoka had been very quiet. 

It was usually very easy to know where he was in the apartment: he hummed, he laughed, he spoke to himself, he drummed his fingernails on the countertops and the walls. A quiet Hisoka almost always meant something sinister was going on.

Illumi stood, bracing his hands on his--slightly wider now--hips. 

“Hisoka,” Illumi called, padding down the hall. He saw the door to their bedroom was slightly ajar. 

“Hisoka,” Illumi said again, peering in. His face turned bright red. 

“Hey, darling,” Hisoka purred, splayed out on their bed like a centerfold. 

“I told you we weren’t--” Illumi choked as Hisoka spit on his palm and then rubbed his hand up his cock casually. 

“That’s  _ mine _ ,” Illumi snapped. 

“You can watch,” Hisoka said with a grin. He spread his--Illumi’s legs--and scooted up on the bed, resting his back against the headboard. 

“We agreed that--”

“No, you  _ told _ me that we weren’t masturbating. You should know by now that I don’t do well with being told what to do. Come and sit down, darling.” Illumi sat on the edge of the bed and watched, throat bobbing, as he jerked himself off. Hisoka was slow in his movements, measured, like he wanted it to last a long time. 

“ _ Hisoka, _ ” Illumi said weakly as he reached over to their bedside table and produced a bottle of lube. 

“You wanna fuck me?”

“You can’t just offer me to fuck myself!” Illumi snarled. Hisoka pulled him into a kiss. 

“Don’t you want to?” 

“That’s gross,” Illumi said into Hisoka’s mouth without heat. 

“Then… can I fuck you?” 

“I don’t want to get fucked by myself either, Hisoka.” Illumi’s voice was flat and sour now, like tepid water.

“Oh, come on, you mean you’ve never fantasized about railing yourself?” Hisoka leaned further back into the pillows and spread his legs a bit wider. He had put his hair in a tight ponytail at the top of his head. It fell to one side, brushing his cheek. 

“No, I haven’t,” Illumi bit out. He was trying to keep his gaze on Hisoka’s face, but his eyes kept wandering downward. It was strange to see his own dick being jerked off. Hisoka was slower and looser with his movements, Illumi noticed, and he kept running his thumb over the head, teasing himself. 

“I bet it would be therapeutic to fuck yourself, just to get a little bit of that self-loathing out,” Hisoka added. 

“What self-loathing?” Illumi sneered. His cheeks heated up as Hisoka cocked his head and clucked his tongue. On Illumi’s face, it looked obscene. 

“Oh, come on, don’t play coy.”

“Do you want to have sex or not?” Illumi asked coldly. Hisoka grinned, a disturbing look with Illumi’s mouth and his teeth. Illumi rather liked the look of it though, and he decided then that he would smile with teeth more. 

“Take me,” Hisoka said with a dramatic sigh, flopping back on the pillows. Illumi, instinctively, reached up to tie his hair into a ponytail and then froze when he realized he didn’t need to. 

“Ditz,” Hisoka said fondly, eyes glittering with amusement. Illumi snorted, settling on his knees between Hisoka’s legs and bracing his left hand on Hisoka’s hipbone. 

“For the record,” Illumi said seriously, picking up the lube from the duvet and coating two of his fingers in it. “I’m not doing this to ‘fuck the self-loathing out’ or whatever you said.” 

“Mhm,” Hisoka said, taking his--Illumi’s--hair out of its ponytail and letting it fan out over the pillow. Usually blank black eyes were alive with a kind of delight and smugness only Hisoka produce. He was, little by little, turning Illumi’s body into the kind that radiated emotion. 

It was frightening. 

Illumi warmed the lube briefly and then leaned forward, propping his body over Hisoka’s with his dry hand, while slowly pushing into him with two fingers. 

Their noses were an inch apart. Illumi could smell bubblegum and the lingering traces of poisoned tea on Hisoka’s breath. 

Hisoka suddenly grunted underneath him, brows knit together. 

“Ha,” he breathed, mostly to himself. “It feels different when it’s not my body.” 

Illumi pressed a gentle kiss to his throat, then another to his jaw, and a final one at the corner of his mouth, his own mouth. 

With a little sigh of satisfaction, Hisoka grinded back down on Illumi’s fingers, encouraging Illumi to start to move them. 

Technically, he was fingering himself, and that should have made it easier. 

Technically. 

He was doing it now from an angle he never had before, and Hisoka wouldn’t sit still, and Illumi was, for the first time in a long time, nervous. He was never nervous to have sex with Hisoka, unless it was one of those times Hisoka insisted on bringing a weird, new sex toy to their bedroom. 

Illumi buried his face into Hisoka’s neck, bracing his shoulder against the mattress on one side so he could free up his other hand. He thumbed gently over Hisoka’s nipple, pulling a soft, breathy sound of surprise from him. It was an Illumi sound, through and through. 

For some reason, that seemed to comfort Illumi. He nibbled at his own neck, snorting fondly as Hisoka laughed breathlessly. So being ticklish was, in part at least, all in your head. 

Illumi curled his fingers, confident in what he was looking for. His own muscled chest tensed underneath him. Hisoka’s hands splayed out and then dug into the mattress. 

“Hah…” he gasped dazedly, hips bucking up against Illumi’s. Illumi took that as a sign to slip in a third finger. 

Illumi lifted himself back up, so he could stare at his own face. 

It was obscene. 

Hisoka was ten times more expressive than Illumi was during sex. His mouth was half-parted, cheeks stained pink. Sweat was starting to weigh at his hairline. He flashed Illumi a smile, just a blink kiss of teeth and then it was gone. 

“My fingers feel good,” Hisoka said hoarsely, still smiling, but without teeth, just smug, full lips. Illumi made a face. 

“Don’t give yourself the credit,” he said, twisting his fingers for good measure. Hisoka’s smile melted off his face and his breath hitched. 

“I’m ready,” he rasped. 

“Just a bit longer,” Illumi replied, brows furrowing in concentration. He wrapped his free hand around Hisoka’s cock, stroking it up and down very gently, just to relieve some pressure. 

Hisoka melted like a pad of butter. He stretched his arms overhead and sighed languidly, body stretching obscenely. Illumi’s body. 

“Let’s just have sex,” he cooed. Illumi shook his head. He wasn’t going to let Hisoka’s masochist tendencies during sex ruin  _ his  _ body. Hisoka’s cock was a little wider than Illumi’s was, and that meant that when Illumi usually fucked him, Hisoka was used to needing less prep, and Illumi was used to performing less prep. 

But they were in different bodies now. 

Illumi didn’t stop until he could fit in four fingers and Hisoka was fucking himself down on them desperately, an arm thrown over his eyes, teeth biting down on his lip. 

“Okay,” Illumi said with a shaky sigh. He stared into his own eyes as he slicked himself up with lube. 

He wondered, briefly, inappropriately, what his parents would think of him fucking himself. Kikyo would be horrified, certainly. Silva, Illumi had a feeling, would be weirdly intrigued by the power dynamic of it. He’d want to turn sex into politics like he had turned murder into an enterprise. 

“Ready?” Illumi asked softly. Hisoka rolled his eyes, gold disappearing under eyelids before reappearing as bright as ever. 

“I have been ready for--” Illumi pressed himself in. 

He had been right to take his time with the prep. Hisoka whimpered, nails digging into Illumi’s hips. 

“Ah, fuck,” he said breathlessly to the ceiling. 

“Sorry,” Illumi said, burying himself to the hilt with a shaky groan. 

“I should have thought about that,” Hisoka admitted with an ego-less laugh. “You’re the biggest out of all my previous partners, so I’m not used to taking anything more.” Illumi preened a little at that, all the while making shallow, gentle thrusts. 

“You can go harder,” Hisoka said, grinning again now. “I’m used to it.” 

“Are you sure?” Illumi asked, leaning in close to his boyfriend’s face, brows knit together with concern. Hisoka kissed the wrinkle between his eyes. 

“Yes.” 

That was, really, all Illumi needed. He snapped his hips forward, sighing in relief at the sensation. He had been so focused on Hisoka, he had forgotten about himself. 

Without realizing, Illumi’s thrusts began to intensify, deeper and faster. He dug his hand into his own long hair, jerking his head up and back. 

His own eyes, black and soulless, were screwed shut, pathetic sounds escaping his throat. He held himself by the hair so hard that he worried, briefly, that he would leave himself with a bald spot if they ever switched back, but he didn’t really care. 

All Illumi could see below him was himself.

His pale chest was flushed pink and heaving. His own self jerked at the grip in his hair, searching for a kiss. Illumi obliged after a moment, kissing Hisoka with barely-contained frenzy. 

His hips ached from the thrusting, thighs trembling. 

Hisoka let out a quiet hiccup, eyes glazed over properly now. 

“I hate you,” Illumi hissed in his face, teeth bared. His grip in his black hair shifted down to Hisoka’s throat, pale and tender and unmarked. With Hisoka’s hands, it was easy to wrap fully around it, fingertips nearly touching on the other side. 

Hisoka gurgled out something, but Illumi couldn’t hear it. 

“I hate you,” he said again, gasping now. All he could see was himself, disgusting black eyes and his mother’s nose and his father’s brow. Of course, somewhere, in the back of his jumbled mind, he knew that the person below him wasn’t actually  _ him.  _

It was Hisoka. 

And he didn’t hate Hisoka at all. 

But the back of his mind wasn’t doing much of the steering now. 

“ _ I hate you, _ ” he gasped out one more time, chest shuddering with almost-sobs. 

“Illumi,” Hisoka croaked gently. 

“ _ You aren’t good enough, _ ” he snarled at himself, spit flying, taking his face with his hand wrapped around his chin. His thrusts became punishing in their strength, probably because that’s what he intended them to be: a punishment. 

“You failed as a brother, you failed as a Zoldyck! You can’t even--” 

“Illumi,” Hisoka said again, louder, voice firm despite the rough quality. His hand wrapped around Illumi's, removing it from his chin. 

“You can’t even  _ kill people  _ correctly,” Illumi half-sobbed. “I hate your fucking face. I hate you!” He slammed his fists down onto his own chest, as if trying to break in. It was a weak attempt, however: Hisoka took both wrists and pulled them away, taking with them the only thing supporting Illumi’s weight. 

As a result, Illumi collapsed forward, right on top of Hisoka, still shaking with furious sobs. He screamed, once, still seething, still trembling with a previously untapped rage. 

“I hate you,” he said against Hisoka’s neck. Hisoka’s hands--his hands--stroked up his spine soothingly. He could feel wetness between their stomachs, slippery and cooling fast. 

Illumi erection was starting to flag. 

“ _ Hisoka _ ,” he finally croaked, realizing with mounting horror that the Illumi he had just brutalized wasn’t actually him. 

“Hey, baby,” Hisoka said softly, voice a little hoarse, hand still running up and down Illumi’s spine. 

“Are you alright?” Illumi asked after a bout of silence. 

“Of course I am. I could have stopped you, you know.” Yes, he did know. 

“I’m sorry,” Illumi said, peeling his sticky face off Hisoka’s neck with a grunt of disgust. 

Hisoka reached out gently and touched his fingertips to Illumi’s cheek, staring at the wetness that stuck to them when he pulled his hand away. 

“I should cry more often,” Hisoka said appreciatively. He tried and failed to smooth out Illumi’s wayward hair. There was a cowlick sticking up that Hisoka’s hair usually did not have: Illumi’s fault, then. 

Illumi’s eyes were heavy, his broad back rising and falling with slow, exhausted breaths. Hisoka stood up on wobbly legs, wincing slightly. 

“I’m not really sure who should be doing the aftercare for who right now,” Hisoka said from the bathroom, “but I’ve decided to start first.” He plopped back down onto the bed and rolled Illumi onto his stomach. His eyes were red and puffy, his pink, bitten lips trembling. 

“I’m guessing that wasn’t as therapeutic as I made it seem,” Hisoka said a little guiltily. Illumi snorted weakly, sighing as Hisoka ran a hot, damp cloth up his neck. 

“I didn't scare you, did I?” 

“Nothing scares me,” Hisoka said with a grin. “It was actually a huge turn on.” 

“Of course it was.”

“In fact, I think we should go another round.” Illumi shoved him gently, righting himself with a sigh. 

“I’m going to run you a bath, don’t get up.” Hisoka stretched out like a cat, listening fondly as Illumi turned on the water and then mumbled to himself about which bath oils to use. 

For all his intimidation and seriousness, Illumi spoke to himself about as much as he spoke to actual people. 

“Hisoka,” Illumi said, peering into the bedroom. His eyes looked better, a little less red, and he wasn’t quite so flushed. 

“Hm?” Hisoka asked tiredly. 

“It just occurred to me a hot bath may not be a good idea. You’re all--I scratched you up.” 

“Hot water’s fine. Carry me.” Hisoka stretched out both arms, waiting for Illumi to scoop him up. 

Hisoka was light when he was in Illumi’s slighter body, and Illumi felt like the strongest thing in the world with Hisoka’s arms. He set him down into the bath as gently as he could manage, and then sank down next to him. 

Hisoka sighed in relief, lowering under the water until he was taking up most of the space and all that could be seen of him were his eyes. Illumi curled up at the end of the tub, watching guilty as Hisoka scrubbed dried blood off his body. 

“Quit it,” Hisoka chided. His eyes were serious when his gaze met Illumi’s. “It was my suggestion. I was expecting something along those lines. I know you. Stop acting like you did a terrible thing.” 

“You expected that of me?” Illumi asked incredulously. Hisoka tapped Illumi’s nose--his nose--and laughed. 

“Don’t worry about it. Lather me up, please.” He placed a sweet-smelling body wash in Illumi’s hand and presented his body like it was a sacrificial offering, smiling soft and sweet. 

* * *

“I don’t want to change back,” Illumi said into the quiet of their bedroom. The bath had gone on for an hour, until the water cooled and they scrambled out, pruned and pale, laughing like children at summer camp. 

Hisoka turned his head to glance at Illumi. His lips twitched into a wry, knowing smile. 

“I don’t either. I’m going to miss looking into the mirror and liking what I see.” 

“Shut up,” Illumi said, without aggression. “Don’t say that.” 

“It’s true,” Hisoka said with a shrug. Illumi fisted his hands in their bedding. 

“It shouldn’t be,” he added, rolling onto his stomach to peer at Hisoka. His usual stares had lost their effect without the help of his big black eyes, but he made do. 

“You’re perfect,” he said sternly, face very serious, very solemn. Hisoka laughed, chest rumbling like an earthquake with Illumi’s cadence, another thing Illumi had gotten from Silva. 

“We’re super messed up.” 

“Whatever,” Illumi said fiercely. 

“I guess all this just means we love each other a lot.” Hisoka’s voice was quiet, searching. 

“Obviously,” Illumi said, throwing an arm around Hisoka’s waist. 

They fell asleep like this, pressed together at nearly every point, noses tucked into necks, fingers tangled loosely together. Their sleep was so deep that Illumi didn’t wake, even when his hair came back long and silky, and Hisoka didn’t wake when his shoulders broadened and freckles appeared all over his back. 

* * *

In the morning, there was little fanfare. Hisoka got up, stretching his shoulders with a purr, and went to the kitchen to make Illumi some tea. Illumi braided his hair lazily, glancing down at the fingerprint-shaped bruises he had given himself on the insides of his knees. 

“And we’re back,” Hisoka said from just outside the bedroom, reappearing with two steaming mugs. Illumi took his with a hum of appreciation, sipping it apprehensively. 

A single black eye cracked open accusingly. 

“This wasn’t poisoned.” 

“No,” Hisoka agreed. 

“You know--” 

“Give yourself a break,” Hisoka said gently. “Enjoy some normal tea for a change.” 

Illumi took another sip, less apprehensive, and sighed. 

“Good?” Hisoka asked. 

“Good,” Illumi agreed, setting down the mug and dropping back into bed. His hair fanned out around him like a halo. Hisoka played with it absently. 

“You know, it’s a lot more fun to play with your hair when it’s attached to you.” 

“Hm,” Illumi said, eyes closing as Hisoka ran a hand through his scalp. 

“I missed looking at you,” Illumi said after a moment, eyes still closed. Hisoka scoffed. 

“Of course.” 

“A mirror wasn’t the same.” 

“I know,” Hisoka said, less smug now. He smiled his own smile, full lips turning up, eyes crinkling. Illumi blinked blearily and stared up at him, then he looked down at himself, the scratched-up chest that was his own doing, the ends of his hair, which reminded him he needed a haircut. 

“Finish your tea,” Hisoka said, tapping Illumi’s bottom lip. “I’m going to go put on my makeup.” 

**Author's Note:**

> id love to hear what you thought!! comments make my day :) peace!


End file.
